Operating Instructions

List of parameters
Parameters
1-311
© Siemens AG 2008 - 2013 All Rights Reserved
SINAMICS G120 CU230P-2 Control Units List Manual (LH9), 01/2013
Description: Compound braking current is used to define the amount of DC current that is produced on stopping the motor dur-
ing U/f operation to further increase the DC brake function.
Compound braking is a superimposition of the DC brake function with regenerative braking (net braking along the
ramp) after OFF1 or OFF3. This permits braking with controlled motor frequency and minimum power input into the
motor. Effective braking without using additional hardware components is obtained by optimizing the ramp down
time and compound braking.
Dependency: The compound braking current is only activated if the DC link voltage exceeds the threshold value in r1282.
Compound braking does not operate:
- when DC braking is active (refer to p1230, r1239)
- as long as the motor is not magnetized (e.g. for flying restart)
- for vector control (p1300 >= 20)
- for synchronous motors (p0300 = 2xx)
Caution: Generally, increasing the braking current improves the braking effect when stopping the motor. However, if the
value is set too high, then the drive can be tripped (shut down) as a result of overcurrent or ground fault.
Recommendation: p3856 < 100 % x (r0209 - r0331) / p0305 / 2
Compound braking generates a current in the motor with a ripple manifesting the rotational frequency. The higher
the braking current is set, the higher the resulting ripple, especially when the Vdc(max) control is simultaneously
active (refer to to p1280).
Note: The parameter value is entered relative to the rated motor current (p0305). Compound braking is deactivated with
p3856 = 0%.
Description: Displays the status word of the compound braking.
Dependency: Refer to: p3856
Description: Sets the signal source to activate the essential service mode (ESM) via digital input.
BI: p3880 = 1 signal:
The essential service mode is activated.
BI: p3880 = 0 signal:
The essential service mode is deactivated.
Dependency: Refer to: p3881, p3882, p3883, p3884, r3887, p3888, r3889
p3856[0...n] Compound braking current / Compound I_brake
PM240 Access level: 3 Calculated: - Data type: FloatingPoint32
Can be changed: U, T Scaling: PERCENT Dyn. index: DDS, p0180
Units group: - Unit selection: - Func. diagram: -
Min Max Factory setting
0.00 [%] 250.00 [%] 0.00 [%]
r3859.0 CO/BO: Compound braking status word / Compound Br ZSW
PM240 Access level: 3 Calculated: - Data type: Unsigned32
Can be changed: - Scaling: - Dyn. index: -
Units group: - Unit selection: - Func. diagram: -
Min Max Factory setting
- - -
Bit field: Bit Signal name 1 signal 0 signal FP
00 Compound braking active Yes No -
p3880 BI: ESM activation signal source / ESM act s s
Access level: 3 Calculated: - Data type: U32 / Binary
Can be changed: U, T Scaling: - Dyn. index: -
Units group: - Unit selection: - Func. diagram: 7033
Min Max Factory setting
- - 0